Numerous machines and methods are available for forming so-called rumble strips along roadways. Rumble strips are provided at the margins of the driving lane so that, when encountered by the wheels of a vehicle, the vehicle is vibrated and sound is generated to inform the driver that the vehicle has wandered from the driving lane. A rumble strip can be in one of two forms. It can be a series of elongate raised ribs spaced apart along the length of the road, or a rumble strip can also be a series of elongate grooves in the roadway. A rumble strip can be formed in either the shoulder material or in the surface of the roadway itself, depending on the need. The rumble strips can be positioned adjacent to each other to provide a constant rumble, or they can include periodic spacing that provides an interrupted rumble when driven over.
In the case of the rumble strip being in the form of a series of spaced apart grooves, they are formed by a machine that cuts the grooves after the shoulder or roadway is formed. Because the cutter has to be raised and lowered to effect formation of spaced apart grooves, large generally vertical force has to be applied to both lift the cutter out of a formed groove and lower the cutter into the surface being cut. These forces cause reactive forces to the machine, often causing violent bouncing of the machine carrying the cutter head and the operator. Also, there are generally horizontal forces being applied to the cutter head because of the engagement of the cutter head with the pavement during cutting. Generally horizontal reactive forces are applied to machine.
Rumble strip forming machines are often single function dedicated machines that, when not in use, are an unnecessary expense to the owner/operator. They also tend to require a separate transport device to move them to the worksite and to unload them. Then, when the work is complete, they require loading back onto the transport device for transportation back to storage. This increases the cost of operation to the owner/operator.
There is thus a need for an improved apparatus for cutting rumble strips in pavement. There is also a need for a rumble strip forming machine that provides a smoother profile to the formed area to reduce or prevent tires from catching against the sides of the ground profile when crossed.